1. Field of the Invention
The invention relates to a disc reproducing apparatus which can reproduce a CD-I disc on which image data and the like in addition to audio data are recorded.
2. Description of the Prior Art
There has been proposed a CD-I (CD Interactive) system in which image data (natural image, animation, computer graphics, etc.), text data, program data, and the like in addition to audio data are recorded onto a CD (Compact Disc) and which can execute the operation in an interactive manner. Since such a CD-I system has a reproducing function of characters, images, audio data, computer data, etc., it can be used in AV industrial apparatuses mainly for the purpose of audio and video fields, electronic publishing which mainly handles characters, data base services mainly comprising information files, education and amusement which are mainly executed by interactive responses, and the like. Thus, the CD-I system is expected as a medium of a new format.
In the CD-I system, various specifications are predetermined so that it can be widely spread as a home-use system while maintaining compatibility. That is, in the CD-I system, a CPU of the 68000 type (microprocessor of 16 bits developed by Motorola Inc.) is used and an operating system which is fundamentally based on widespread OS9 is used as a real-time operating system which handles various kinds of files. Two trigger buttons and an X-Y device are used as an input device. Two audio and video systems are prepared as an output system. The CD-I player is constructed so that it can reproduce ordinary compact disc music.
As mentioned above, the CD-I player can reproduce not only a CD-I disc but also an ordinary compact disc for music (CD-DA disc). However, in the CD-I player, it is determined that two trigger buttons and an X-Y device are used as an input device. All of the operations must be performed by using at least those two trigger buttons and the X-Y device. Therefore, in the conventional CD-I player, even when a CD-DA disc is reproduced, the operations must be performed by the two trigger buttons and the X-Y device.
Therefore, there is considered a method whereby the operation keys of PLAY, STOP, AMS (Auto Music Scan), and the like which are used when reproducing a compact disc for musics are displayed on an initial screen of an LCD display, and when a CD-DA disc has been loaded, the operations of the operation keys which are displayed on the screen are executed by using two trigger buttons and an X-Y device. In the case of the CD-I disc, however, since those operation keys which are displayed are unnecessary, if the operation keys are always displayed as long as the CD-I disc has been loaded, the user becomes confused.
In the case of reproducing a CD-DA disc, since there is no need to display on the screen, there is considered a method whereby the LCD display is turned off and an electric power consumption is reduced. However, in the case where the operations to reproduce the CD-DA disc are executed by using two trigger buttons and an X-Y device while observing the screen, if the LCD display is turned off, an inputting operation cannot be performed.